1. Pattern Pattern Materials
Pattern is duplicate of the component manufactured by casting material.
Pattern Materials
Wood
Metals
Plasters
Plastics and Rubbers
Waxes

2. Types of Patterns
Types of Patterns Used in Sand Casting: (a)solid pattern (b)split pattern (c)match‑ plate pattern (d)cope and drag pattern (e)gated pattern (f)loose piece pattern (g)sweep pattern (h)shell pattern

3. Solid Pattern (Single Piece)

4. Split Pattern

5. Cope and Drag Pattern

6. Match Plate Pattern

8. Pattern Allowances
Pattern Allowances 1.Shrinkage allowance 2.Draft allowance 3.Finish allowance 4.Shake allowance 5.Distortion allowance

9. Core and Core Making
Core is part used in casting processes to produce internal cavities.
Requirements of Core
There must be adequate strength for handling.
In the hardened state it must be strong enough to handle forces of casting.
Permeability must be very high to allow for the escape of gases
Good refractoriness is required as the core is usually surrounded by hot metal.
A smooth surface finish
A minimum generation of gases during metal pouring.

10. Core Making Process Purpose of Core For hollow casting
Used to strengthen the moulds
Core Making process
Core Sand Preparation
Core Making
Core Baking
Core Finishing

11. Types of cores i)According to the shape and position of the Core
Horizontal, Vertical ,Hanging ,Balanced
ii)According to the state or condition of core
Green Sand , Dry Sand
iii)According to the type of core hardening process employed
Hot box , Cold set, Cast able Sand, Oil-No-Bake Process

12. Core Boxes Core box is basically a pattern for making cores
Core boxes are employed for ramming core in them
Core boxes impart the desired shape to the core sand
Types of core boxes
Half core box
Slab or Dumb Core box
Gang Core Box
Loose Piece Core Box